Just six months after she was reunited with her former Big Breakfast partner Johnny Vaughan on the Capital 95.8 breakfast show, Denise Van Outen has left the station.

Vaughan is now looking for his fourth co-presenter on the show since he succeeded Chris Tarrant in the Capital breakfast hot seat in 2004.

It was supposed to be a dream reunion with Van Outen six years after they last presented Channel 4's Big Breakfast together.

But her arrival failed to lift the show's ratings above its rivals – it is third in the London breakfast wars behind Magic 105.4 and Heart 106.2 - and Van Outen was reported to find the early starts clashed with her TV work.

In a statement, the station's parent company GCap Media, which was bought by Global Radio in a £375 million deal earlier this year, said Van Outen had asked for a meeting with the new management within three days of the takeover in June.

"Denise asked for a meeting and made it clear to her new bosses that she wasn't able to handle the early starts as they were impacting on her personal life and her health," said a GCap Media spokesman.

"It takes a special kind of person to consistently rise early and give the public the level of entertainment they expect each morning. Denise requested the opportunity to break her contract immediately and we obliged."

The spokesman added: "Johnny was an integral part of the initial decision to bring Denise into the show. I think he was surprised to learn she couldn't cope with the early starts."

Van Outen joined the show in February but the pair failed to recreate the chemistry that characterised their time together on the Big Breakfast, and she leaves six months into a 12-month contract.

Vaughan is currently presenting the show alongside model Lisa Snowden, although she is not expected to replace Van Outen on a permanent basis.

Van Outen was Vaughan's third co-presenter in three and a half years, after original sidekick Becky Jago and Zoe Hanson.

Vaughan and Van Outen had an average weekly reach of 772,000 between 6am and 9am in the second quarter of this year, down 7.6% year on year and 6.9% on the previous quarter, according to the latest official Rajar listening figures.

They were behind the number one London commercial breakfast show, Magic's Neil Fox, with 868,000 listeners in the same time period, and Heart's Jamie Theakston and Harriet Scott, with an average weekly audience of 844,000.

Capital, previously the undisputed number one commercial station in London, slipped to fourth place for the first time in the ratings last year, behind Magic, Heart and dance station Kiss.

The station has lost audience ever since Tarrant's high profile departure four years ago and has continued to slide despite - or perhaps because of - a string of relaunches in recent years.

Bauer Radio's Magic has now been the number one commercial station in London for six successive quarters with an average weekly reach of more than 2 million.

Heart 106.2, also part of the Global Radio group, is in second place with 1.77 million. Capital reclaimed the third spot from Bauer's Kiss with 1.6 million.

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